Humans age dramatically in two bursts: At 44 and 60
A groundbreaking study has discovered that human aging is not a gradual process, but occurs in at least two accelerated bursts. The research, led by Professor Michael Snyder from Stanford University, tracked thousands of molecules in individuals aged between 25 and 75 years. It identified two significant waves of age-related changes around 44 and again at 60. This finding could potentially explain why certain health issues like musculoskeletal problems and cardiovascular diseases (CVDs) tend to surface at specific ages.
Dramatic changes in mid-40s and early 60s
The study involved monitoring 108 volunteers over a period of one to nearly seven years. The participants provided blood and stool samples, as well as skin, oral, and nasal swabs. Researchers analyzed 135,000 different molecules (proteins, RNA, and metabolites) and microbes (the bacteria, fungi, viruses living in the guts or on the skin of the participants). Snyder stated that "We're not just changing gradually over time. There are some really dramatic changes."
Mid-40s aging spike observed in both genders
The study initially attributed the mid-40s aging spike to perimenopausal changes in women potentially influencing the results for entire group. However, further analysis revealed similar shifts occurring in men during their mid-40s. Dr. Xiaotao Shen, former postdoctoral scholar at Stanford medical school and first author of the study, suggested that "while menopause or perimenopause may contribute to the changes observed in women in their mid-40s, there are likely other, more significant factors influencing these changes in both men and women."
Age-related changes linked to disease risk and metabolism
The first wave of age-related changes included molecules associated with CVDs and the metabolism of caffeine, alcohol, and lipids. The second wave involved molecules related to immune regulation, kidney function, and carbohydrate metabolism. Molecules connected to skin and muscle aging altered at both time points. These findings align with previous research indicating that the risk of many age-related diseases does not increase incrementally but shows a steep rise after 60.
Lifestyle factors may influence aging process
The study also suggested that some of the observed changes could be related to lifestyle or behavioral factors. For example, an increase in alcohol consumption during people's mid-40s, often a stressful period of life, could potentially affect alcohol metabolism. Snyder emphasized the importance of adjusting our lifestyles while we're still healthy and suggested that these findings could help target interventions such as increasing exercise during periods of rapid muscle loss.
